Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Model for new generation of blood vessels challenged

02.06.2009
In-growth and new generation of blood vessels, which must take place if a wound is to heal or a tumor is to grow, have been thought to occur through a branching and further growth of a vessel against a chemical gradient of growth factors.

Now a research team at Uppsala University and its University Hospital has shown that mechanical forces are considerably more important than was previously thought. The findings, published today in the journal Nature Medicine, open up a new field for developing treatments.

New generation of blood vessels takes place in normal physiological processes, such as when a wound heals, children grow, or the mucous membrane of the womb is built up to be able to receive a fertilized egg. It is also a crucial mechanism in tumor diseases, rheumatism, and certain eye disorders, for example.

How new generation and in-growth of blood vessels takes place has not been fully understood. It has been assumed that the mechanisms are the same as those that occur in embryonic development, which is probably a great over-simplification. The formation of the vascular system in the fetus takes place in a well-organized and reproducible way, which means that we all have blood vessel systems that look very much the same. On the other hand, new generation of vessels in wound healing and tumor growth, for example, occurs in a chaotic environment where it is difficult to see that there would be well-defined gradients of growth factors, and it has not been possible to find evidence of any.

"Unlike these previous models, our findings show that in wound healing, in-growth of new blood vessels takes place via mechanical forces that pull already existing blood vessels into the wound when it heals," says Pär Gerwins, who directed the study and is a physician and interventional radiologist at Uppsala University Hospital as well as a researcher with the Department of Medical Biochemistry and Microbiology at Uppsala University.

It has long been known that specialized connecting tissue cells, so-called myofibroblasts, wander in and pull the wound together. In the study being published it is shown that this wound contraction governs the in-growth of new blood vessels. Since it is a matter, at least initially, of the expansion of already existent blood vessels that have continuous blood circulation, there is a rapid in-growth of fully functional vessels, which is what we see when a wound heals.

The study not only explains a fundamental biological mechanism but also provides clues for new therapeutic goals in treating various diseases. Since myofibroblasts exist in relatively large numbers in tumors and rheumatic joints, one potential strategy to try to block the contractive capacity of these connective tissue cells. The new model can also partially explain why treatment of tumor diseases with blood-vessel inhibiting substances has not been as successful as was hoped.

Finally, the model can partially explain the mechanism behind the positive effect of "vacuum-assisted wound closure," (VAC). This is a method of treatment for hard-to-heal wounds where an air-tight bandage is applied and then the pressure is reduced in the wound with the aid of suction, which creates a continuous mechanical pull in the underlying tissue.

Blood-vessel-rich wound-healing tissue is thereby generated much more rapidly, which substantially hastens healing. It is hoped that it will now be possible to understand why some wounds do not heal and also to develop new types of wound treatment.

For more information, please contact: Pär Gerwins, phone: +46 (0)18-471 43 66; cell phone: +46 (0)73-984 82 07, e-mail: Par.Gerwins@imbim.uu.se

Read the article on the Nature Medicine home page.

Anneli Waara | idw
Further information:
http://www.vr.se
http://www.nature.com/nm/journal/vaop/ncurrent/abs/nm.1985.html

More articles from Life Sciences:

nachricht Cnidarians remotely control bacteria
21.09.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Immune cells may heal bleeding brain after strokes
21.09.2017 | NIH/National Institute of Neurological Disorders and Stroke

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Comet or asteroid? Hubble discovers that a unique object is a binary

21.09.2017 | Physics and Astronomy

Cnidarians remotely control bacteria

21.09.2017 | Life Sciences

Monitoring the heart's mitochondria to predict cardiac arrest?

21.09.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>